Table 1.
Summary of growth, thermoregulatory, and indirect calorimetry measures.
| Measure | Thermal Neutral | Heat Stress | Interaction | Time Effect | Temperature Effect | ||
|---|---|---|---|---|---|---|---|
| Pre | Post | Pre | Post | ||||
| Weight (kg) |
15.3 ± 1.1 | 18.9 ± 1.3 * | 15.1 ± 0.7 | 19.8 ± 1.0 * | 0.0884 | <0.0001 | 0.8039 |
| Rectal Temp. (°C) |
39.3 ± 0.1 | 39.2 ± 0.1 | 39.4 ± 0.1 | 39.6 ± 0.1 *t | 0.0084 | 0.2828 | 0.0470 |
| Respiratory Rate (B.P.M.) |
57 ± 2 | 56 ± 2 | 55 ± 1 | 94 ± 4 *t | <0.0001 | <0.0001 | <0.0001 |
| Feed Intake (kg/day) |
1.1 ± 0.1 | 1.3 ± 0.2 * | 1.1 ± 0.1 | 1.2 ± 0.1 | 0.6355 | 0.0025 | 0.8439 |
| RER (CO2expired:O2consumed) |
0.95 ± 0.03 | 0.97 ± 0.01 | 0.91 ± 0.02 | 1.02 ± 0.02 * | 0.0026 | 0.0004 | 0.8731 |
| DEE (kcal) |
1090 ± 120 | 1252 ± 238 | 1038 ± 48 | 992 ± 123 | 0.3110 | 0.5267 | 0.3434 |
| DEE/BW (kcal/kg) |
70.9 ± 5.1 | 67.5 ± 11.6 | 68.8 ± 1.7 | 49.7 ± 4.8 * | 0.2111 | 0.0368 | 0.2366 |
Pigs were acclimated under thermoneutral conditions (14 h light/10 h dark, 21.6 ± 0.8 °C, with humidity 46–64%) for five days prior to treatment (Pre). Pigs were then randomly assigned (n = 8 per group) to thermal neutral (TN, 22.0 ± 0.4 °C, with humidity 43–63%) or heat stress (HS, 33.6 ± 0.5 °C, with humidity 22–40%) treatment groups for five days (Post). DEE (daily energy expenditure), RER (respiratory exchange ratio). p-values were generated with two-way repeated measures ANOVA. (*) indicates time effect within treatment (p < 0.05). (t) indicates a temperature effect within time point (p < 0.05).